Urgent — same day vet contact
Within days
Lungworm in dogs
Coughing, breathing difficulty, unexplained bleeding, or sudden weakness in a dog who eats slugs or snails needs urgent vet review for lungworm (Angiostrongylus vasorum).
Recognise the signs
- Cough, breathing difficulty
- Tiring quickly
- Unexplained bleeding (gums, nose, cuts that won't stop)
- Pale gums
- Behavioural change, seizures (severe cases)
- Sometimes asymptomatic until severe
First aid steps
- Phone the vet — bloods and faecal testing.
- Note any known slug/snail interaction.
Do NOT
- Do not assume routine wormer covers it — many do not.
- Do not let dogs play with toys left outdoors overnight (slug trails).
When to phone the vet immediately
- Bleeding that won't stop
- Sudden severe weakness, seizures
- Breathing difficulty
Common causes
- Eating slugs and snails (deliberately or accidentally on toys, bowls, grass)
- UK-wide but particularly south of England, Wales, southern Scotland
What the vet will need to know
- Current wormer (and active ingredient)
- Known slug/snail access
- Bleeding episodes
Aftercare
- Specific anti-lungworm treatment (e.g. moxidectin spot-on, fenbendazole course).
- Supportive care for bleeding or breathing issues.
- Continue prevention.
Prevention
- Vet-prescribed lungworm-active wormer year-round (e.g. milbemycin-containing).
- Lift water bowls and toys overnight.
- Discourage slug eating.
Frequently asked questions
Does my normal wormer cover lungworm?
Many over-the-counter wormers do not. Confirm with the vet — milbemycin, moxidectin and a few others have lungworm activity.
Is lungworm fatal?
Untreated severe cases can be. Treatment is highly effective when given in time.
Where is it most common?
South and west of the UK, with cases now reported nationwide. Consider risk regardless of location.